there was an article in QST (circa 1992 IIRC?) on adapting the astatic
d104 microphone using a single dual op amp, setup for 300 to 3,000 hz pass
band, for impedance conversion to 600 ohms output impedance. Some d104
mikes had an adapter built-in using a 9 volt battery, one recently sold on
Ebay ($21-ish) with the mike ;-)

hth bobm
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* Robert Monaghan POB 752182 Southern Methodist Univ. Dallas Tx 75275 *
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